Solution

Consistent with our goals, SBPF partnered with the town of Nantucket to implement erosion control efforts in the winter of 2013-2014 and since that has increased the number of geotube layers from 3 to 4, planted vegetation and installed a drainage system to limit the impact of surface runoff and delivered thousands of dump truck loads of sand to assure that there is no negative impact on surrounding beaches. (For more detail, see TIMELINE). Ultimately, SBPF would like to extend this approach to protecting the entire bluff from the end of Baxter Road at the Sankaty Lighthouse property to the point at which erosion has begun (with bank erosion beginning at around 63 Baxter Road and dune erosion occurring farther south around 53 Baxter Road).

AUDIO TOUR

Listen to our Audio Tour, highlighting the major aspects of the erosion control project at Sconset Bluff, by calling 508-443-6443.

GEOTUBES

What are geotextile tubes?

Geotextile tubes or geotubes are giant sausages made of extremely durable plastic mesh filled with sand. Each geotube is about 19 feet wide, 7 feet high and 100-200 feet long. The geotubes are stacked in four layers or tiers along the base of the bluff and prevent further erosion. They are covered with a thick layer of sand delivered to the site from island pits that is designed to wash away during storms. This “sacrificial” sand is replaced every year. For now, geotubes protect 950 feet of the most endangered section of the bluff.

Is the geotube and sand replacement project working?

For the third year in the row, since the geotubes were installed in January 2014, there has been zero erosion from the base of the bluff and no harm done to area beaches. The sacrificial sand contributed more sand than would have eroded from the unprotected bluff. With the addition of a storm water drain at the edge of Baxter Road last fall, erosion from the top of the bluff has now also been stopped. American beachgrass planted on the face of the bluff has also helped reduce erosion caused by wind and rain.

Project Monitoring

’Sconset Beach has been professionally surveyed annually since 1994 to track changes along a six-mile stretch of beach and adjacent bluff area from the ’Sconset sewer beds to Wauwinet. The results are documented in a series of public reports from experts at the Woods Hole Group. The project is monitored after every large storm to check the geotubes, the sand coverage on the geotubes and the unprotected beach. SBPF reports its findings throughout the year to the Nantucket Conservation Commission.